Depending on the breed of pheasant, some are 23 some are longer 28 ,if you temp is fluctuating that much you could also have some problems, you want to keep it at a steady 99.5 if you can
The temp does need to be consistent. I had a little giant incubator years ago and I never got one to hatch. If nothing pips tomorrow I would crack one open. I had way to many problems with that incubator. Sorry to bring the bad news I know exactly how you are feeling.
I have a little giant that I use for chicken eggs and it is an absolute pain to keep temp steady in but it holds a lot of eggs and is cheap! But you definitely need to watch temp as much as you can because they do tend to fluctuate a lot!